1. Field of Invention
The invention is directed to bottom hole assemblies having a mill or cutting tool rotatably driven by a hydraulically actuated motor in the bottom hole assembly to abrade or cut away an object disposed in oil and gas wells, and in particular, to bottom hole assemblies disposed on wireline that permit axial movement of a portion of the bottom hole assembly below an anchor point within the well to facilitate engagement of the mill or cutting tool with the object.
2. Description of Art
In the drilling, completion, and workover of oil and gas wells, it is common to perform work downhole in the wellbore with a tool that has some sort of cutting profile interfacing with a downhole structure. Examples would be milling a downhole metal object with a milling tool or cutting through a tubular with a cutting or milling tool. Such milling may be necessary to remove an object or “fish” disposed within the wellbore. In general, milling operations are performed using a mill tool attached to threaded pipe or coiled tubing through which a fluid such as drilling mud is pumped. The fluid causes a hydraulically actuated motor disposed above the mill tool to rotate which, in turn, causes the mill tool to rotate and the object to be abraded or cut away. To facilitate cutting, a hydraulically actuated anchor can be included in the threaded pipe or coiled tubing string to stabilize the string within the well.